Hybrid materials for organic solvent nanofiltration and pervaporation membranes

Abstract

Embodiments of the present disclosure describe polymer blend membranes comprising a layer including a polymer blend of regenerated cellulose and polydimethylsiloxane and a support in contact with the layer. Embodiments of the present disclosure describe methods of preparing a polymer blend membrane comprising contacting a cellulose precursor and a PDMS precursor in a solvent to form a polymer blend solution, depositing the polymer blend solution on a surface of a suitable support, curing the PDMS precursor of the polymer blend solution to form PDMS, and converting the cellulose precursor to cellulose to form a polymer blend membrane including cellulose and PDMS. Embodiments of the present disclosure describe methods of separating chemical species by one or more of organic solvent nanofiltration and pervaporation.

1 . A method of preparing a membrane, comprising:
 contacting a cellulose precursor and a polydimethylsiloxane (PDMS) recursor in a solvent to form a polymer blend solution;   depositing the polymer blend solution on a surface of a suitable support;   curing the PDMS precursor of the polymer blend solution to form PDMS; and   converting the cellulose precursor to cellulose to form a polymer blend membrane including cellulose and PDMS.   
     
     
         2 . The method of  claim 1 , wherein the cellulose precursor is a cellulose functionalized with trimethylsilyl (TMS), dimethylsilyl (DMS), triethylsilyl (TES), triisopropylsilyl (TIPS), t-butyldimethylsilyl (TBS/TBDMS), or t-butyldiphenylsilyl (TBDPS). 
     
     
         3 . The method of  claim 1 , wherein the cellulose precursor is trimethylsilyl cellulose (TMSC), dimethylsilyl cellulose (DMSC), triethylsilyl cellulose (TESC), triisopropylsilyl cellulose (TIPSC), t-butyldimethylsilyl cellulose (TBDMSC), or t-butyldiphenylsilyl cellulose (TBDPSC). 
     
     
         4 . The method of  claim 1 , wherein the PDMS precursor includes a pre-polymer and a crosslinker. 
     
     
         5 . The method of  claim 1 , wherein the solvent is an organic solvent. 
     
     
         6 . The method of  claim 1 , wherein the polymer blend solution is a compatible miscible polymer blend. 
     
     
         7 . The method of  claim 1 , wherein the polymer blend solution exhibits no visible phase separation. 
     
     
         8 . The method of  claim 1 , wherein the suitable support is a polymeric support. 
     
     
         9 . The method of  claim 1 , wherein the PDMS is functionalized with end groups selected from the group consisting of vinyl, hydride (—H), methyl (—CH 3 ), 3-aminopropyl (—CH 2 CH 2 CH 2 NH 2 ), glycidyl ether (—CH 2 CH 2 CH 2 OCH 2 ), hydroxyl (—OH), alkyhydroxy (—(CH 2 ) m OH), chloride (—Cl), or stearate 
       
         
           
           
               
               
           
         
       
     
     
         10 . The method of  claim 1 , wherein the PDMS is a copolymer with functional groups selected from the group consisting of hydride (—H), 3-(2-(2-hydroxyethoxy)ethoxy)propyl (—CH 2 CH 2 CH 2 (OCH 2 CH 2 ) 2 OH), poly(ethylene glycol) methyl ether (—CH 2 CH 2 CH 2 O(CH 2 CH 2 O) n  CH 3 ), 3-aminopropyl, —CH 2 CH 2 CH 2 NH 2 , and polyacrylates. 
     
     
         11 . The method of  claim 1 , wherein the polymer blend membrane includes regenerated cellulose. 
     
     
         12 . The method of  claim 1 , wherein the polymer blend membrane comprises a layer including a polymer blend of cellulose and PDMS and a support in contact with the layer. 
     
     
         13 . The method of  claim 1 , wherein the converting is achieved by one or more of vapor-phase hydrolysis, reintroducing active hydrogen, immersion in 1M hydrochloric acid solution, and hydrolysis with boiling water and simple alcohols. 
     
     
         14 . A method of separating chemical species by organic solvent nanofiltration, comprising:
 contacting a first side of a polymer blend membrane with a feed stream containing one or more solutes dissolved in an organic solvent; and   collecting a permeate from a second side of the membrane;   wherein the polymer blend membrane comprises a layer including a polymer blend of regenerated cellulose and PDMS and a support in contact with the layer.   
     
     
         15 . The method of  claim 14 , wherein the first side of the polymer blend membrane includes the layer including the polymer blend of regenerated cellulose and PDMS. 
     
     
         16 . The method of  claim 14 , wherein the organic solvent includes one or more of isopropanol, ethanol, acetonitrile, tetrahydrofuran, toluene, chloroform, hexane, methanol, and acetone. 
     
     
         17 . The method of  claim 14 , wherein a concentration of the regenerated cellulose ranges from about 25 wt % to about 75 wt % of the total polymer concentration of the polymer blend membrane. 
     
     
         18 . A method of separating chemical species by pervaporation, comprising:
 contacting a first side of a polymer blend membrane with a liquid feed stream containing one or more solvents; and   collecting a permeate in a vapor or gas phase from a second side of the membrane;   wherein the polymer blend membrane comprises a layer including a polymer blend of regenerated cellulose and PDMS and a support in contact with the layer.   
     
     
         19 . The method  claim 18 , wherein the first side of the polymer blend membrane includes the layer including the polymer blend of regenerated cellulose and PDMS. 
     
     
         20 . The method of  claim 18 , wherein the liquid feed stream includes water and ethanol.